Note 1 - Nature of Operations (Details Textual) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jan. 31, 2020	Jul. 31, 2019	Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2016	Jul. 31, 2014
Revenue from Contract with Customer, Including Assessed Tax	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0
Cash, Cash Equivalents, and Term Deposits	10,300
Working Capital	$ 9,900
Entity Incorporation, Date of Incorporation	May 16, 2003

Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration